ABSTRACT Numerous studies have documented racial & ethnic disparities in sleep deficiency among adolescents & adults. These disparities are thought to be explained partially by experiences of interpersonal racial discrimination. What remains lacking is knowledge of the causal mechanisms linking structural racism to poor sleep health. The long-term goal is to reduce racial disparities in health. The scientific objective of this application is to determine the extent to which structural racism, as manifested in racial disparities in police use of deadly force, leads to racial disparities in sleep health. This application focuses on police use of deadly force on unarmed black Americans as a cardinal manifestation of structural racism. The central hypothesis is that police use of deadly force on unarmed black Americans leads to unhealthy sleep among other black Americans in the general U.S. population. This hypothesis has been formulated on the basis of strong preliminary data showing that police use of deadly force on unarmed black Americans leads to poor mental health among other black Americans in the general U.S. population. The rationale for this application is that detailed understanding of the causal mechanisms linking structural racism to poor sleep health is likely to offer a strong scientific framework for developing and targeting structural and psychosocial interventions to reduce racial disparities in sleep, cardiometabolic, and other health outcomes. The central hypothesis will be tested by pursuing three specific aims: 1) Estimate the extent to which police use of deadly force on unarmed black Americans is causally associated with poor sleep health among other adult black Americans in the general U.S. population. 2) Estimate the extent to which police use of deadly force on unarmed black Americans is causally associated with poor sleep health among other children and adolescent black Americans in the general U.S. population. 3) Elaborate a conceptual framework identifying the mechanisms that link racial disparities in police use of deadly force to racial disparities in sleep health. In Aims 1 & 2, population-based survey data from 2013-18 will be merged with novel, high-resolution geocoded data on police killings and analyzed using quasi-experimental regression models. In Aim 3, qualitative interviews will be conducted in 5 U.S. cities to build a grounded theory about structural racism and sleep health. Potential mediating pathways, and effect modification by age and sex, will be explored in all aims. The key innovation of the proposed research is to pair quasi-experimental, population-based studies with qualitative research to investigate a novel contributor to racial disparities in sleep health. The findings will have significant public health impact because they will provide proof of principle for development and targeting of structural and psychosocial interventions to reduce racial disparities in sleep health.